672
FXUS66 KSEW 110340
AFDSEW
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
840 PM PDT THU SEP 10 2026
SYNOPSIS
TROUGHING DEVELOPING OVER THE AREA WILL CONTINUE INTO THIS
WEEKEND, BRINGING UNSETTLED CONDITIONS AND COOLER TEMPERATURES
TO THE REGION. RIDGING LOOKS TO REBUILD THROUGH THE FIRST HALF
OF NEXT WEEK FOR A SLOW WARMING TREND.
SHORT TERM /TONIGHT THROUGH SATURDAY NIGHT/
AN UPPER LEVEL TROUGH OVER THE REGION WILL BRING ONSHORE FLOW,
COOLER TEMPERATURES, AND UNSETTLED WEATHER TO WESTERN WASHINGTON
OVER THE NEXT COUPLE OF DAYS. AS TROUGHING DEEPENS INTO FRIDAY,
AN UPPER LEVEL LOW WILL DEVELOP OFFSHORE OF VANCOUVER ISLAND.
ANOTHER ROUND OF MORNING CLOUDS ON FRIDAY WITH A SLIGHT CHANCE
OF DRIZZLE IN THE MORNING. DRY CONDITIONS THROUGH FRIDAY WITH
HIGH TEMPERATURES ONCE AGAIN IN THE UPPER TO LOWER 70S ACROSS
THE REGION. THE UPPER LEVEL LOW WILL MOVE ONSHORE ON SATURDAY,
BRINGING WIDESPREAD RAIN SHOWERS TO TO THE REGION. ADDITIONALLY,
THERE IS A 15-25% CHANCE OF THUNDERSTORMS, PRIMARILY SOUTH OF
SNOHOMISH COUNTY AT TIMES THROUGHOUT THE AFTERNOON. WINDS MAY BE
BREEZY AT TIMES IN AND AROUND SHOWERS. HIGH TEMPERATURES REMAIN
IN THE MID TO UPPER 60S, WHILE OVERNIGHT LOWS STAY IN THE MID
50S.
LONG TERM /SUNDAY THROUGH THURSDAY/
CONDITIONS LOOK TO START
DRYING OUT INTO SUNDAY, WITH SOME LINGERING SHOWERS LIKELY IN
THE CASCADES AND THE OLYMPICS. AN UPPER LEVEL RIDGE WILL BEGIN
TO BUILD OFFSHORE ON MONDAY, INTRODUCING A SLOW WARMING TREND
THROUGH MIDWEEK. SOME ENSEMBLES SUGGEST WEAK TROUGHING
TUESDAY/WEDNESDAY THAT COULD BRING SOME POPS TO THE REGION, BUT
FOR NOW, LOOKS LIKE DRY AND WARM CONDITIONS WILL MANIFEST.
MAZURKIEWICZ
AVIATION
NORTHWESTERLY FLOW ALOFT THIS EVENING AND OVERNIGHT BEFORE TURNING
MORE ZONAL MID-MORNING FRIDAY. MANY TERMINALS SEEING LIGHT AND
VARIABLE WINDS THIS EVENING WHILE THE REMAINDER TYPICALLY SEEING
SOUTHWESTERLY TO WESTERLY WINDS GENERALLY 4 TO 8 KTS. MODELS
CONTINUE TO SUGGEST THAT MAJORITY OF TERMINALS SHOULD FAVOR A MORE
SOUTHWESTERLY FLOW WITH SPEEDS IN THE LATTER RANGE VERY LATE TONIGHT
AND CARRYING THROUGH INTO LATE FRIDAY AFTERNOON.
WIDESPREAD VFR CONDITIONS PERSIST OVER W WA THIS EVENING. ISOLATED
MVFR CONDITIONS ARE PRESENT ALONG THE COAST AND CURRENT SATELLITE
IMAGERY /AS OF 03Z/ SHOWS ISOLATED PATCHES OF LOWER CIGS BEGINNING
TO DEVELOP HERE AND THERE. POST-FRONTAL ONSHORE FLOW SHOULD BE
ENOUGH TO NURTURE CIGS FALLING THROUGHOUT THE OVERNIGHT PERIOD WITH
WIDESPREAD MVFR TO ISOLATED IFR CONDITIONS IN PLACE BY 12-15Z EARLY
FRIDAY MORNING. RECOVERY TO VFR CONDITIONS WILL BE SLOW WITH
TERMINALS BREAKING OUT AROUND 20Z OR 21Z FRIDAY AFTERNOON AND
REMAINING THERE FOR THE REST OF THE TAF PERIOD.
KSEA...VFR CIGS THIS EVENING GRADUALLY LOWERING OVERNIGHT TO MVFR BY
12-14Z AND REMAINING THERE FOR THE REMAINDER OF THE MORNING AND INTO
EARLY AFTERNOON. LATER BREAKOUT AKIN TO EARLIER THURSDAY WITH CIGS
RETURNING TO VFR AFTER 20Z. CLOUDS CONTINUE TO LIFT AND BREAK UP FOR
REMAINDER OF TAF PERIOD, BUT NOT CLEARING OUT COMPLETELY. LIGHT AND
VARIABLE WINDS THIS EVENING AND EARLY TONIGHT BEFORE INCREASING
SLIGHTLY IN SPEED FROM THE SW...GENERALLY 4-8 KTS...AND STAYING
THERE FOR MUCH OF FRIDAY.
18
MARINE
POST-FRONTAL WINDS STILL SEEING OCCASIONAL GUSTS UP TO 25 KTS THIS
EVENING AND AS SUCH, INHERITED SMALL CRAFT ADVISORY WILL CONTINUE
THROUGH 5 AM FRIDAY MORNING FOR BOTH WINDS AND SEAS OF 8 TO 11 FT.
ANOTHER FRONTAL SYSTEM WILL MOVE ACROSS THE WATERS FRIDAY INTO
SATURDAY. NEITHER IMPACTFUL WINDS NOR SEAS ARE EXPECTED WITH THIS
SYSTEM, ALTHOUGH PORTIONS OF THE SOUTHERN INTERIOR AND COASTAL
WATERS WILL HAVE A 20% CHANCE OF SHOWERS AND THUNDERSTORMS FROM THIS
SYSTEM. CONDITIONS WILL BECOME MORE BENIGN GOING INTO NEXT WEEK AS
HIGH PRESSURE REBUILDS OVER THE COASTAL WATERS. SEAS DECREASE THIS
WEEKEND INTO NEXT WEEK DOWN TO 4-6 FT.
HPR/18
FIRE WEATHER
A RETURN TO ONSHORE FLOW WILL MAINTAIN COOLER AND MORE MOIST
CONDITIONS ACROSS WESTERN WASHINGTON THROUGH THE WEEKEND. LIGHT
PRECIPITATION IS LIKELY LATE FRIDAY INTO SATURDAY AS ANOTHER
WEAK SYSTEM MOVES OVER THE REGION. CONDITIONS ARE EXPECTED TO
GRADUALLY WARM AND DRY INTO NEXT WEEK, THOUGH FIRE WEATHER
CONCERNS REMAIN LOW AT THIS TIME.
SEW WATCHES/WARNINGS/ADVISORIES
WA...NONE.
PZ...SMALL CRAFT ADVISORY UNTIL 5 AM PDT FRIDAY FOR COASTAL WATERS
FROM CAPE FLATTERY TO JAMES ISLAND 10 TO 60 NM-COASTAL
WATERS FROM JAMES ISLAND TO POINT GRENVILLE 10 TO 60 NM-
COASTAL WATERS FROM POINT GRENVILLE TO CAPE SHOALWATER 10
TO 60 NM.
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